Which description best summarises the type of government system that exists in Nigeria today?

Introduction / Context:
This general knowledge question asks about the form of government in Nigeria. Modern states can be described using several overlapping terms based on their constitutional structure, such as federal or unitary, republican or monarchical, parliamentary or presidential. Nigeria combines more than one of these features, and the exam tests whether you recognise that all of them apply simultaneously.

Given Data / Assumptions:

The options describe Nigeria as federal, as a republic and as having a presidential system.
The last option, All of the above, suggests that all three characteristics may be true together.
Nigeria has a written constitution and a complex political history, but the question targets its broad contemporary structure.
We assume the question refers to Nigeria political system in the modern era, not during colonial rule.

Concept / Approach:
A federal state divides powers between a central government and regional units such as states or provinces. A republic is a system in which the head of state is elected, not a hereditary monarch. A presidential system is one where the president is both head of state and usually head of government, with separate election from the legislature. Nigeria fits all three descriptions it is a federal republic operating under a presidential model of governance. Therefore, the correct answer must be the combined option that recognises all these aspects.

Step-by-Step Solution:
Step 1: Recall that Nigeria is divided into states and has a constitution that distributes powers between the central government and these states, which makes it a federal country.Step 2: Recall that Nigeria does not have a king or queen as head of state but instead has an elected president, which is typical of a republic.Step 3: Recall that the president in Nigeria is elected separately from the legislature and serves as chief executive, indicating a presidential system rather than a purely parliamentary one.Step 4: Evaluate each individual option and see that each captures one correct feature of Nigeria political system.Step 5: Evaluate option D, All of the above these features apply to Nigeria, which combines all three accurate descriptions into a single comprehensive statement.Step 6: Conclude that option D is the best and most complete answer.

Verification / Alternative check:
To verify, think about how Nigeria is commonly described in textbooks and news reports. It is often referred to as the Federal Republic of Nigeria, which already signals both its federal structure and its republican form. Additionally, discussions about Nigerian politics frequently mention the role of the president, presidential elections and separation of powers, which are hallmarks of a presidential system. This triple description confirms that federal, republic and presidential all apply together, supporting the combined answer.

Why Other Options Are Wrong:
Option A, Federal, is incomplete because it leaves out the facts that Nigeria is also a republic and uses a presidential system.
Option B, Republic, is incomplete for the same reason, as it does not mention the federal and presidential characteristics.
Option C, Presidential system, is also incomplete because it ignores the federal structure and the republican nature of the state.

Common Pitfalls:
One common mistake is to think that you must choose only one label and therefore pick the first correct sounding option. Another pitfall is believing that descriptions such as federal and presidential are mutually exclusive, when in reality many countries combine them. In multiple choice questions, whenever a state genuinely fits several categories, exam setters often provide an All of the above option to reward students who recognise the full picture.

Final Answer:
The correct answer is All of the above these features apply to Nigeria. Nigeria is a federal republic that operates a presidential system of government.